Operating Segments (Narrative) (Details) - Operating Segments $ in Millions	9 Months Ended
Sep. 30, 2023 USD ($)
Corporate and Other
Segment Reporting Information [Line Items]
After- tax net income	$ 23
Dominion Energy South Carolina, Inc. [Member]
Segment Reporting Information [Line Items]
After- tax net income	21
Benefit related to real estate transactions	31
Benefit related to real estate transactions, after tax	$ 23

Profit loss from real estate operations after tax.

No definition available.

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- Definition

The aggregate amount of income or expense from ancillary business-related activities (that is to say, excluding major activities considered part of the normal operations of the business).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 220
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.7)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483621/220-10-S99-2

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- Definition

The net cost of operation of other real estate (including provisions for real estate losses, rental income, and gains and losses on sales of real estate).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 220
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-04.14(d))
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147483589/942-220-S99-1

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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